==================================================================
BUG: KCSAN: data-race in data_push_tail / string

write to 0xffffffff870a31a0 of 1 bytes by task 11895 on cpu 0:
 string_nocheck lib/vsprintf.c:647 [inline]
 string+0x17b/0x220 lib/vsprintf.c:725
 vsnprintf+0xb57/0xe80 lib/vsprintf.c:2782
 vscnprintf+0x3e/0x80 lib/vsprintf.c:2888
 printk_sprint kernel/printk/printk.c:2092 [inline]
 vprintk_store+0x5f2/0xb50 kernel/printk/printk.c:2206
 vprintk_emit+0xcc/0x430 kernel/printk/printk.c:2252
 vprintk_default+0x22/0x30 kernel/printk/printk.c:2282
 vprintk+0x7f/0x90 kernel/printk/printk_safe.c:50
 _printk+0x76/0x96 kernel/printk/printk.c:2292
 __ext4_error_inode+0x293/0x3a0 fs/ext4/super.c:807
 __ext4_ext_check+0x4f6/0x860 fs/ext4/extents.c:485
 ext4_ext_check_inode+0x42/0x50 fs/ext4/extents.c:501
 __ext4_iget+0x1bcd/0x1cd0 fs/ext4/inode.c:4986
 __ext4_fill_super fs/ext4/super.c:5244 [inline]
 ext4_fill_super+0x4397/0x5010 fs/ext4/super.c:5517
 get_tree_bdev+0x2b4/0x3b0 fs/super.c:1323
 ext4_get_tree+0x18/0x20 fs/ext4/super.c:5547
 vfs_get_tree+0x49/0x190 fs/super.c:1530
 do_new_mount+0x200/0x650 fs/namespace.c:3040
 path_mount+0x4ad/0xbb0 fs/namespace.c:3370
 do_mount fs/namespace.c:3383 [inline]
 __do_sys_mount fs/namespace.c:3591 [inline]
 __se_sys_mount+0x281/0x2d0 fs/namespace.c:3568
 __x64_sys_mount+0x63/0x70 fs/namespace.c:3568
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffffffff870a31a0 of 8 bytes by task 11891 on cpu 1:
 data_make_reusable kernel/printk/printk_ringbuffer.c:590 [inline]
 data_push_tail+0x10f/0x440 kernel/printk/printk_ringbuffer.c:675
 data_alloc+0xbc/0x2b0 kernel/printk/printk_ringbuffer.c:1046
 prb_reserve+0x897/0xbd0 kernel/printk/printk_ringbuffer.c:1555
 vprintk_store+0x51c/0xb50 kernel/printk/printk.c:2196
 vprintk_emit+0xcc/0x430 kernel/printk/printk.c:2252
 vprintk_default+0x22/0x30 kernel/printk/printk.c:2282
 vprintk+0x7f/0x90 kernel/printk/printk_safe.c:50
 _printk+0x76/0x96 kernel/printk/printk.c:2292
 __ext4_msg+0x174/0x180 fs/ext4/super.c:944
 __ext4_fill_super fs/ext4/super.c:5246 [inline]
 ext4_fill_super+0x43c7/0x5010 fs/ext4/super.c:5517
 get_tree_bdev+0x2b4/0x3b0 fs/super.c:1323
 ext4_get_tree+0x18/0x20 fs/ext4/super.c:5547
 vfs_get_tree+0x49/0x190 fs/super.c:1530
 do_new_mount+0x200/0x650 fs/namespace.c:3040
 path_mount+0x4ad/0xbb0 fs/namespace.c:3370
 do_mount fs/namespace.c:3383 [inline]
 __do_sys_mount fs/namespace.c:3591 [inline]
 __se_sys_mount+0x281/0x2d0 fs/namespace.c:3568
 __x64_sys_mount+0x63/0x70 fs/namespace.c:3568
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x000000010002ed22 -> 0x635f7478655f3474

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 11891 Comm: syz-executor.0 Not tainted 6.0.0-syzkaller-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
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EXT4-fs (loop0): mount failed